Muhammed Kermali1, Raveena Kaur Khalsa1, Kiran Pillai1, Zahra Ismail1, Amer Harky2
As of the 28th April 2020, the COVID-19 pandemic has infiltrated over 200 countries and affected over three million confirmed people. We review different biomarkers to evaluate if they are able achieve an earlier diagnosis, predict clinical outcomes and correlate with the severity of COVID-19 disease.
Materials and Methods
A literature search was conducted using electronic search engines and databases. Keywords to refine the search included ‘COVID-19’, ‘SARS-CoV2’, ‘Biomarkers’ among others. Exclusion criteria were primarily studies with no particular definition of role of biomarkers in COVID-19. Only relevant articles are cited for each section.
Results
Thirty-four studies were deemed relevant, which reviewed multiple biomarkers. Of these C-reactive protein, serum amyloid A, interleukin-6, lactate dehydrogenase, neutrophil-to-lymphocyte ratio, D-dimer, cardiac troponin, renal biomarkers, lymphocytes and platelet count levels were highlighted as key markers of COVID-19 infection. There were significantly higher levels of these biomarkers in patients dealing with severe COVID-19 infection barring two. Platelet count and neutrophil-to-lymphocyte ratio were seen to be significantly decreased in severe infections. Out of all of the biomarkers changes in C-reactive protein, D-dimers and platelet count were shown to be strongly associated with mortality.
Conclusions
Biomarkers are a necessity of monitoring clinical care, but research is still in the early stages of the COVID-19 outbreak. The most useful biomarkers from early research seem to be C-reactive protein, D-dimer and platelet count. Although many studies produced reproducible findings, there is a pressing need for further research into biomarkers with larger sample sizes across several centres is required for definitive conclusions on whether biomarkers that have prognostic value.
